Noise-induced local heatings in microbeam analysis
Résumé
Heatings produced by the irradiation with light ion microbeams were measured in situ by using microthermocouples deposited and etched onto a SiO2 glass substrate. For a given distance r between the microbeam centre and the thermocouple, we show that the heating averaged over the irradiation time decreases as 1/r, in agreement with theory. Moreover, we report strong heating random fluctuations close to the beam resulting from the fluctuations of the beam intensity. We show that, close to the beam, these heating fluctuations dominate largely over the averaged heating, as predicted by the theory of heat propagation with a random source.